The present invention relates to an improved anchor assembly of the type generally described in U.S. Pat. No. 4,075,924 issued to Thomas McSherry et al. on Feb. 28, 1978. The '924 patent describes an anchor assembly comprising a pair of elongated leg members of flexible material and an elongated anchor member coupled to adjacent end portions of the legs. The legs are shown spaced apart along the long dimension of the anchor member. The leg members include resilient means such as transversely bent end portions to resiliently bias the anchor member generally transversely to the legs.
In use, the flexible legs are bent so that the long dimension of the anchor member is oriented along the legs and the anchor is inserted into a hole in a wall or ceiling. The transversely bent end portions of the legs then bias the anchor member back to its transverse position, and suitable collar means are slipped up the legs to sandwich the wall between the anchor and the collar.
While this anchor assembly is highly useful for many applications, the presence of resilient biasing means, such as the bent end portions of the legs, and the need for leg flexibility, tend to limit the maximum strength available in the legs of the device.
Another form of anchor assembly is described in U.S. Pat. No. 4,043,245 issued to Stanley Kaplan on Aug. 23, 1977. In the Kaplan device, the legs are spaced apart across the narrow dimension of the anchor member and each leg is coupled to only one side of the anchor member via a trunion inserted into an apertured flange.
The difficulty with this structure is that each leg is held to the anchor member on only one side. Nothing forces the trunion into the aperture and if it pulls out, the leg comes off. Moreover, the spacing of the legs across the narrow dimension of the anchor member limits the minimum size of the anchor and hence requires larger holes in the wall.